This invention generally relates to a manually actuated switching apparatus for engaging electrical contacts to complete an electrical conductive path. Specifically, the invention relates to a push-button switch for electrically completing an electrical circuit in a keyboard apparatus. The switch includes a spring member which serves as both a biasing means for the keytop plunger and as a contact means for completing an electrical conductive path.
Push-button switches have been previously incorporated in keyboards used for selectively interconnecting electrical circuits. For example, these switches may be used in the keyboard of an electronic calculator. However, prior art devices have certain disadvantages such as complexity due to a large number of parts and the resulting high production cost. Another disadvantage of prior art devices is the excessive amount of work required to depress the switches which resulted in finger fatigue for the user. The ambiguity of whether the keytop plunger has been depressed or whether the switch-make point had been achieved is another problem encountered in the prior art devices. Further disadvantages of the prior art include excessive contact bounce upon making contact and surface corrosion of the contacts.
The present invention is designed to overcome the disadvantages of the prior art devices by providing novel features which accomplish certain desired advantages.
It is therefore an object of this invention to provide a simple and low cost push-button switch which may be used in a keyboard.
It is a further object of this invention to provide an improved push-button switch having relatively few and simple parts.
Still another object is to provide a push-button switch wherein less work is required to press the keytop plunger to the switch-make point.
Another object of the invention is to provide a switch actuating mechanism having increased tactile feedback for definitely identifying depression of the keytop plunger and the switch-make point.
A further object of the invention is to provide a switching mechanism having improved electrical characteristics including minimal contact bounce and definite electrical contact between selectively contacting members.
An even further object of this invention is to reduce surface corrosion of contacts while providing a more reliable contact configuration.